Mindfulness training reduces the severity of irritable bowel syndrome in women: results of a randomized controlled trial

Abstract

Objectives: This prospective, randomized controlled trial explored the feasibility and efficacy of a group program of mindfulness training, a cognitive-behavioral technique, for women with irritable bowel syndrome (IBS). The technique involves training in intentionally attending to present-moment experience and non-judgmental awareness of body sensations and emotions.

Methods: Seventy-five female IBS patients were randomly assigned to eight weekly and one half-day intensive sessions of either mindfulness group (MG) training or a support group (SG). Participants completed the IBS severity scale (primary outcome), IBS-quality of life, brief symptom inventory-18, visceral sensitivity index, treatment credibility scale, and five-facet mindfulness questionnaire before and after treatment and at 3-month follow-up.

Results: Women in the MG showed greater reductions in IBS symptom severity immediately after training (26.4% vs. 6.2% reduction; P=0.006) and at 3-month follow-up (38.2% vs. 11.8%; P=0.001) relative to SG. Changes in quality of life, psychological distress, and visceral anxiety were not significantly different between groups immediately after treatment, but evidenced significantly greater improvements in the MG than in the SG at the 3-month follow-up. Mindfulness scores increased significantly more in the MG after treatment, confirming effective learning of mindfulness skills. Participants' ratings of the credibility of their assigned interventions, measured after the first group session, were not different between groups.

Conclusions: This randomized controlled trial demonstrated that mindfulness training has a substantial therapeutic effect on bowel symptom severity, improves health-related quality of life, and reduces distress. The beneficial effects persist for at least 3 months after group training.

Figure 1.

Study flow diagram for mindfulness meditation vs. support group for irritable bowel syndrome, 2006 – 2009. * Of the 64 ineligible subjects, 10 did not meet Rome II criteria for IBS, 9 had too few symptoms to participate in our study, 14 had other bowel illness or surgery in addition to IBS, 3 were pregnant or intended to become pregnant, 9 had excluded medical illness and 12 psychiatric illness, and 7 had prior experience with meditation. In addition, 62 were unavailable to participate: 32 individuals declined to participate during the screening process, largely due to distance to the study site or the time commitment and 30 were eligible and interested, but unable to schedule participation. BSI-18, brief symptom inventory-18; FFMQ, five-facet mindfulness questionnaire; IBS, irritable bowel syndrome; IBS-QOL, irritable bowel syndrome-quality of life; IBS-SS, irritable bowel syndrome severity scale; ITT, intent to treat; VSI, visceral sensitivity index.

Figure 2.

Comparison of changes in overall severity of IBS symptoms (IBS-SS score) in the two intervention groups from pre-treatment baseline to post-treatment and at 3-month follow-up assessments: The figure is based on ITT analysis, and P value shows significance of the timexgroup effect in the repeated-measures ANOVAs. ANOVAs, analyses of variances; IBS, irritable bowel syndrome; IBS-SS, irritable bowel syndrome severity scale; ITT, intent to treat.